Improvement in preserving- wood



(tinted swa ALEXANDER J. SHELDON, 0E BUFFALO, NEW YORK,

Letters Patent No. 106,625, dated August 2 3, 1870 antedated August 12, 187i).

IMP OVE ENT IN passnnvme Woon.

The Schedule referred to in these Letters Patent and making part of the samev process should be continued until the wood is thor onghly permeated by the lye. The time required will, therefore, depend upon the size and nature of the timhel' operated upon, boards one inch thick requiring about one hour.

The action of the caustic lye will dissolve and remove the albumen and hygroscopic matters from the wood, and render it in a proper condition to receive the preservative,compounds, which willtake the. place previously filled by such matters in the pores of the wood. a

Any of the well-known preservative compounds may be used, and applied by injection, under pressure,

or in any other well-known manner. 1

One of the modes which I adopt is to boil the wood,

through the wood. gradually turn it into a carbonate of lime, thereby after the caustic-lye treatment above described, in milk of lime, until the lye becomes disseminated The action of the air upon it will rendering it insoluble, and, in fact, fossiliziug the wood. Or the wood may be immersed -in.a hot solntlou oi sugar of lead until it is impregnated therewith, when,

sulphuric acid being added, an insoluble sulphate of lead willremain in the wood.

The caustic lye may be made fromsoda, as it is the cheapest. Its gravity is immaterial, except as to expense. I have used it as weak as 3 and as high as 30. I a

After the lye becomes charged with woody matters, it can be reclaimed or used as a'manure.

I claim as my iuventiou The process of boiling wood in caustic lye to remove its albumen and hygroscopic matter, and prepare it for the reception of preservative compounds, substantially as hereinbefore set forth. I

ALEXANDER J. SHELDON.

Witnesses:

Issac A.- VERPLAIIGK, GEORGE (i. WEBSTER. 

